coagulation (rus. коагуляция otherwise агрегация; флокуляция) — cohesion of colloidal particles with each other resulting in formation of more complex aggregates.


Coagulation is the process of enlarging particles, and sedimentation is the end result of this process, however, the term "coagulation" is often used to describe this phenomenon as a whole.

Coagulation occurs due to the collision of colloidal particles as a result of Brownian motion, the effects of an electric field, or mechanical stress on the system. Coagulation can also be induced by adding coagulants, substances that accelerate coagulation, in particular, electrolytes. If the content of dispersed particles is high the coagulation structure (gel) can occupy the entire volume. Coagulation is the most typical for dispersions of solids – sols and suspensions. Upon reaching a certain size the colloidal particles become unable to stay in suspension and get isolated from the environment in which they were distributed; sedimentation of the colloid occurs.


  • Eremin Vadim V.
  • Kurochkin Ilya N.


  1. B. V. Nekrasov, Basics of General Chemistry (in Russian). V. 1. 3rd ed. — Moscow: «Khimia» Publisher, 1973. — 656 p.
  2. Coagulation // Chemical encyclopedia (in Russian). V. 2. — Moscow: Sovetskaja ehnciklopedija, 1990. P. 412–413.

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